Radio waves, particularly those of 30 MHz to 3 GHz in the VHF (Very High Frequency) and UHF (Ultra High Frequency) bands used for television broadcasting and mobile communications, function as a social infrastructure indispensable to daily life, and they may be said to be public property from a social point of view. The government, its related agencies and wireless carriers are required to publicize as much information on radio waves as possible so that radio wave users can monitor whether the radio waves are fairly used or not. As public information currently available for users, there are a frequency assignment situation and radio station license information (Non-Patent Literature (NPL) 1), a terrestrial digital broadcasting area map (NPL 2), a cellular phone area map (NPL 3, NPL 4 and NPL 5) and the like.
Patent Literature 1 (PTL 1) discloses a system and a method for creating a distribution map of radio wave intensity by using a positioning function and an electric field strength measurement function of a cellular phone. When a radio wave intensity distribution is known, availability of a radio wave can be assessed on the basis of the distribution. PTL 2 discloses a method which acquires a radio wave intensity distribution by using radio wave intensities acquired at a plurality of discrete observation points by calculation or measurement. In PTL 3, a blind zone building to which no radio wave can reach is extracted from radio wave environment data and geographic data including information about buildings. Then, from data on the usage state of a radio communication system of concern and the geographic data, a calculation formula for estimating the profitability of communications is acquired. On the basis of information on the extracted blind zone building and the acquired calculation formula, a method disclosed in PTL 3 further estimates profitability improvement effects to be achieved by implementing blind zone measures on the blind zone building and, according to the amounts of the improvement effects, performs prioritization of the blind zone measures.